Dianella tasmanica plant named ‘DT23’

ABSTRACT

‘DT23’ is a distinctive variety of  Dianella tasmanica,  which is characterized by its combination of compact form, green leaf color, broad leaf width, strong leaf arching, green summer basal sheath color with red-brown margin, and large bluish-purple berries.

Latin name of the genus and species: The Latin name of the novel varietydisclosed herein is Dianella tasmanica ‘DT23’.

Variety denomination:

The inventive variety of Dianella tasmanica disclosed herein has beengiven the variety denomination ‘DT23’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct variety of evergreenperennial Dianella tasmanica, which has been named ‘DT23’. It isanticipated that the plant of this invention will be marketed under thetradename Emerald Arch. Dianella are a genus of ornamental grass-likeplants in the Phormiaceae family. In general, Dianella tasmanica hasflax-like leaves. Pale blue flowers on stems up to 40 cm high typicallydevelop in spring and early summer and are followed by green berriesthat become bluish-purple.

Lineage: The cultivar ‘DT23’ was discovered in 1996 in Clarendon, NewSouth Wales, Australia, during a seedling selection of cultivatedDianella tasmanica. The new variety originated from open pollinatedparent plants and subsequent selection of a distinctive seedling fromthe resulting progeny as part of a breeding program. The breedingprogram used assisted open pollination with occasional shaking ofinflorescences to promote pollen transfer. The parent (D. tasmanica,ecotype from southern tablelands of new South Wales, Australia) ischaracterized by green leaf color, medium leaf width, medium leafarching, absent to very weak leaf glaucosity, and a red-brown basal leafsheath color. The selection criterion for ‘DT23’ was broad leaf width.

Asexual reproduction: The new variety, Dianella tasmanica ‘DT23’, wasfirst asexually propagated by vegetative division in the state of NewSouth Wales, Australia in September 1997 and has been asexuallypropagated since that time by division and micropropagation. Thedistinctive characteristics of cultivar ‘DT23’ have remained stable andtrue to type through successive cycles of asexual propagation.

SUMMARY OF THE INVENTION

‘DT23’ is a distinctive variety of Dianella tasmanica, which ischaracterized by its combination of compact form, green leaf color,broad leaf blade width, strong leaf arching, green summer basal leafsheath color with red-brown margin and large bluish-purple berries.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an exemplary Dianella tasmanica ‘DT23’ plant atapproximately two years of age.

FIG. 2 shows an exemplary Dianella tasmanica ‘DT23’ plant atapproximately fifteen months of age.

DETAILED BOTANICAL DESCRIPTION OF THE VARIETY

The following is a detailed botanical description of a new and distinctvariety of Dianella tasmanica known as ‘DT23’ based upon observations of15-month-old plants grown in nursery pots in full sun in open beds inClarendon, New South Wales, Australia. Color notations are based on TheRoyal Horticultural Society Colour Chart, The Royal HorticulturalSociety, London, 1995 Edition.

Those skilled in the art will appreciate that certain characteristicswill vary with older or, conversely, with younger plants. ‘DT23’ has notbeen observed under all possible environmental conditions. Wheredimensions, sizes, colors and other characteristics are given, it is tobe understood that such characteristics are approximations or averagesset forth as accurately as practicable. The phenotype of the variety maydiffer from the descriptions set forth herein with variations inenvironmental, climatic and cultural conditions.

‘DT23’ is an evergreen perennial Dianella tasmanica. ‘DT23’ is abroad-bladed, compact plant, with strong leaf arching, green leaf color,green summer basal leaf sheath color with red-brown margin and largebluish-purple berries.

A botanical description of ‘DT23’ and comparisons with other varietiesof Dianella tasmanica are provided below.

Technical Description of the Variety

-   Plant characteristics: Growth habit erect to semi-erect, height    medium, shoot density medium.-   Leaves: Attitude erect to semi-erect, width broad (mean 29 mm),    upper side color yellow-green (RHS 147A), lower side color    yellow-green (RHS 147B), glaucosity weak, shape ligulate, apex    acute, cross-section concave, margin with spines present with medium    prominence, midrib lower side with spines present with strong    prominence.-   Basal sheath: Anthocyanin coloration (summer) red-brown on margin    only.-   Basal shoots: Attitude erect to semi-erect, arrangement cluster.-   Flowers: The flower buds are 8-10 mm long and 3-4 mm wide. Bud color    changes from yellow green (RHS 147B) to violet blue (approximately    RHS 89A) prior to opening. Mature flowers have 6 petals with ovate    shape. Petal color is violet-blue (approximately RHS 94B) in the    centre and violet-blue (approximately RHS 97B) at the margin. Anther    filament color is yellow (approximately RHS 12A). Flower diameter    range is 10-13 mm. Petal attitude is strongly reflexed. Petal length    is 8-9 mm and petal width is 3-4 mm. Petal margin is entire and    texture is smooth. Petal attachment is sessile with an obtuse to    truncate base.-   Fruit: A succulent berry, diameter 8-9 mm, length to 20 mm, shape is    oblong, color of unripe berry is yellow green (RHS 146A) and color    of ripe berry is approximately violet blue (RHS 89A), surface    texture is smooth and glossy. Seed color is black.-   Cultural conditions: ‘DT23’ can tolerate low nutrient conditions; it    does not like continually wet soil conditions, but can tolerate    well-draining sandy soils to very heavy clay soils. ‘DT23’ is fairly    adaptable to a wide range of soil pH.-   Cold and heat tolerance: ‘DT23’ has been observed to be cold    tolerant to −12° C. in Clarendon, New South Wales, Australia.    Foliage color did not change under these conditions, except for a    slight burning at the very tips of the leaves. The plant has also    been grown for two years in Charleston, S.C., USA and has remained    evergreen down to −6° C.

‘DT23’ is also very heat tolerant. It adapted well to the high heatconditions during summer in Clarendon, New South Wales, Australia andhigh heat and humidity conditions during summer in Charleston, S.C., USAwithout any noticeable disease or insect damage.

-   Drought tolerance: ‘DT23’ has very good drought tolerance. ‘DT23’    survived three months without rainfall under hot conditions in    non-irrigated garden beds in summer in Clarendon, Australia. ‘DT23’    has also been grown in non-irrigated beds in Charleston, S.C., USA    for two years, and has been observed to go as long as 30 days    without rainfall.-   Pest resistance: No known pests.

These and other features and characteristics of ‘DT23’ are apparent fromFIGS. 1 and 2.

Comparisons and other Dianella.

‘DT23’ is a more attractive ornamental glass-like plant as compared withthe parent. ‘DT23’ is characterized by a yellow-green leaf color,broader leaf blade, stronger leaf arching, and the presence ofanthocyanin on the basal sheath margin in summer as compared with theparent ‘D. tasmanica’ (ecotype from southern tablelands of New SouthWales, Australia) (see Table 1).

Dianella ‘TR20’ (U.S. patent application Ser. No. 11/238,477, filed Sep.29, 2005) is the most similar comparator variety to ‘DT23’. Incomparison with ‘TR20’, cultivar ‘DT23’ has a green leaf color whereas‘TR20’ is more yellow-green. ‘DT23’ has a wider leaf, has stronger leafarching, and more prominent spines on the lower side midrib than ‘TR20’.‘DT23’ has a green basal sheath color with a red-brown margin in summerwhereas ‘TR20’ has an overall red-brown basal sheath color (see Table1).

A comparative trial of Dianella cultivar ‘DT23’ with ‘TR20’ and theparent D. tasmanica was carried out in summer 2003 to autumn 2004 inClarendon, New South Wales, Australia. Plant observations anddescriptions were taken in autumn 2003. The data are presented in Table1 below. The plants for this trial were propagated from divisions,planted into 130 mm pots filled with soilless potting mix, and movedinto 140 mm pots in full sun for nine months before the trial started.Nutrition was maintained with slow release fertilizers; pest and diseasetreatments were applied as needed. The trial was designed such thattwenty plants of each variety were arranged in a completely randomizedmanner. Measurements were taken from ten plants at random with onesample per plant.

TABLE 1 Dianella Variety Characteristic ‘DT23’ ‘TR20’ D. tasmanica(parent) Plant Height (cm) Mean 34.2 28.0 31.5 Std Deviation 4.5 1.9 5.7LSD/Sig. 4.33 P ≦ 0.01 ns* Leaf Width (mm) Mean 29.1 20.0 21.3 StdDeviation 1.6 1.7 2.0 LSD/Sig. 1.81 P ≦ 0.01 P ≦ 0.01 Leaf GlaucosityWeak Absent-very Absent-very weak weak Leaf lower side Strong MediumMedium midrib: prominence of spines Leaf Color Upper Side 147A 146A 147ALower Side 147B 146B 147B Basal Sheath Color Green with Reddish -Reddish-brown red-brown brown margin Basal Sheath: Weak Medium- Mediumintensity of strong anthocyanin color *ns—not significant

1. A new and distinct variety of Dianella tasmanica plant named ‘DT23’,substantially as described and illustrated herein.